The present invention relates to devices for cleaning and circulating liquids.
There are certain installations which require liquid to be continuously cleaned, the liquid being received by the circulating and cleaning system in a raw form and being cleaned while being circulated and returned to the source of the raw liquid. For example, swimming pools require the liquid thereof to be circulated and cleaned in this manner.
It is already known to provide centrifugal pumps, including self-priming centrifugal pumps, which suck the liquid which is to be cleaned through a strainer while also filtering the liquid before the latter is returned to the source of the raw liquid. In this way it is possible to clean liquids, particularly water.
Systems of the above general type can be used with swimming pools of all types and sizes. Thus, systems of this type are used conventionally with public as well as private swimming pools.
With known installations of the above type, the pump is connected by way of a suitable pipe with the filter device, although a suitable hose may also be used for this purpose. The connection of the filter device to the pump by way of such a pipe or hose is however technically undesirable because of the costs involved, the space required, and the possible source of faulty operation resulting from such a connection. It is to be remembered that when a pipe or hose is used to connect a pump to a filter device, it is also required to provide faultless seals at the connections between the pipe or hose and the pump on the one hand as well as the filter device on the other hand.
As has been indicated above, a further disadvantage of such known systems resides in the relatively large amount of space required thereby. With many installations where it is desired to use a system of the above type, the required space is not available. Up to the present time it has been necessary to mount the pump as well as the filter device on a suitable foundation, most often a foundation which is common to the pump as well as the filter device, such as, for example, a suitable base plate. With such a construction during operation of the pump a considerable amount of undesirable noise is generated, this noise being intensified by the base plate which carries the structure.